From 5e8cf7e339e42bdcf9772fd64b155a3e01ea8356 Mon Sep 17 00:00:00 2001
From: "J. Lewis Muir" <jlmuir@imca-cat.org>
Date: Sun, 26 Jan 2025 21:07:13 -0600
Subject: [PATCH] Add Linux support for external tirpc library

Add support on Linux for using a tirpc library that is not a system
library.
---
 asyn/Makefile            | 11 ++++++++---
 configure/CONFIG_SITE    | 10 ++++++++--
 testGpibApp/src/Makefile |  9 +++++++--
 3 files changed, 23 insertions(+), 7 deletions(-)

diff --git a/asyn/Makefile b/asyn/Makefile
index 3f803f489..231380434 100644
--- a/asyn/Makefile
+++ b/asyn/Makefile
@@ -31,10 +31,15 @@ asyn_SYS_LIBS_WIN32 = ws2_32 winmm
 asyn_SYS_LIBS_cygwin32 = $(CYGWIN_RPC_LIB)
 
 # Some linux systems moved RPC related symbols to libtirpc
-# Define TIRPC in configure/CONFIG_SITE in this case
+# Set TIRPC* variables in configure/CONFIG_SITE in this case
 ifeq ($(TIRPC),YES)
-  USR_INCLUDES_Linux += -I/usr/include/tirpc
-  asyn_SYS_LIBS_Linux += tirpc
+  USR_INCLUDES_Linux += -I$(TIRPC_INCLUDE)
+  ifeq ($(TIRPC_EXTERNAL),YES)
+    tirpc_DIR = $(TIRPC_LIB)
+    asyn_LIBS_Linux += tirpc
+  else
+    asyn_SYS_LIBS_Linux += tirpc
+  endif
 endif
 
 SRC_DIRS += $(ASYN)/asynDriver
diff --git a/configure/CONFIG_SITE b/configure/CONFIG_SITE
index 538cd55ce..754af8756 100644
--- a/configure/CONFIG_SITE
+++ b/configure/CONFIG_SITE
@@ -55,8 +55,14 @@ DRV_FTDI_USE_LIBFTDI1=NO
 #EPICS_LIBCOM_ONLY=YES
 
 # Some linux systems moved RPC related symbols to libtirpc
-# To enable linking against this library, uncomment the following line
-# TIRPC=YES
+# To enable linking against this library, set TIRPC=YES
+TIRPC=NO
+# If TIRPC_EXTERNAL=NO, libtirpc is a system library; otherwise, it is not
+TIRPC_EXTERNAL=NO
+# Path to the include files for libtirpc
+TIRPC_INCLUDE=/usr/include/tirpc
+# If TIRPC_EXTERNAL=YES, path to the library files for libtirpc
+TIRPC_LIB=
 
 -include $(SUPPORT)/configure/CONFIG_SITE
 
diff --git a/testGpibApp/src/Makefile b/testGpibApp/src/Makefile
index 20957003d..665321223 100644
--- a/testGpibApp/src/Makefile
+++ b/testGpibApp/src/Makefile
@@ -43,8 +43,13 @@ testGpibVx_SRCS_vxWorks += testGpibVx_registerRecordDeviceDriver.cpp
 testGpib_LIBS += devTestGpib
 testGpib_LIBS += testSupport asyn
 ifeq ($(TIRPC),YES)
-  USR_INCLUDES += -I/usr/include/tirpc
-  testGpib_SYS_LIBS += tirpc
+  USR_INCLUDES += -I$(TIRPC_INCLUDE)
+  ifeq ($(TIRPC_EXTERNAL),YES)
+    tirpc_DIR = $(TIRPC_LIB)
+    testGpib_LIBS += tirpc
+  else
+    testGpib_SYS_LIBS += tirpc
+  endif
 endif
 SYS_PROD_LIBS_cygwin32 += $(CYGWIN_RPC_LIB)
 testGpib_LIBS += $(EPICS_BASE_IOC_LIBS)